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Meridional deflection of global eddy propagation derived from tandem altimetry: Mechanism and implication

Science China Earth Sciences 2024年第3期67卷 811-825页

作者： Ge chen Xiaoyan chen Frontiers Science Center for Deep Ocean Multispheres and Earth System School of Marine TechnologyOcean University of ChinaQindao 266100China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQindao 266237China

A common view on meridional deflection of eddy propagation is poleward for cyclones and equatorward for anticyclones. This widely accepted polarity-sensitive pattern has been increasingly undermined given that it is systematically violated on both zonal and regional scales as recently reported. Here, we approach the problem by exploring these violations in terms of eddy effects of spatiotemporal geostrophy, thermal fading, and flow dragging, yielding the following main conclusions.(1) The polarity-dependent deflection discrepancy is a pseudo feature resulting from a biased fit to the normalized eddy tracks which are spatially asymmetric(though azimuthally symmetric) between the two signs;Instead, the primary pattern of eddy deflection appears to be geographically correlated and polarity independent.(2) Geostrophic adjustment plays a critical role in defining the meridional movement of an eddy. Specifically, a consistent poleward(equatorward) trajectory bending of spatially(temporally) ageostrophic eddies is observed irrespective of their polarity.(3) The mechanism of eddy deflection is also determined by its zonal propagation direction. Westward propagating eddies are substantially affected by thermal fading, while opposite ones by flow dragging. A realistic and comprehensive understanding of eddy deflection mechanisms serves as a significant contribution to the prediction of eddy trajectory, and the protection of ocean environment.

关键词： Mesoscale eddies Eddy propagation Eddy meridional deflection Satellite observation Geostrophic adjustment

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超高效液相色谱-电喷雾串联质谱法同时测定地表水中28种皮质激素

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色谱 2018年第11期36卷 1158-1166页

作者：龚剑林粲源熊小萍陈迪云陈永亨吴翠琴广州大学环境科学与工程学院珠江三角洲水质安全与保护省部共建教育部重点实验室广东省放射性核素污染控制与资源化重点实验室广东广州510006

建立了同时测定地表水中28种皮质激素的超高效液相色谱-电喷雾串联质谱(UHPLC-ESI-MS/MS)的分析方法。水样经HLB柱固相萃取、C_8反相色谱柱分离,在动态多反应监测(DMRM)模式下采用电喷雾离子化正、负离子模式(ESI±)进行信号采集与测定... 详细信息

建立了同时测定地表水中28种皮质激素的超高效液相色谱-电喷雾串联质谱(UHPLC-ESI-MS/MS)的分析方法。水样经HLB柱固相萃取、C_8反相色谱柱分离,在动态多反应监测(DMRM)模式下采用电喷雾离子化正、负离子模式(ESI±)进行信号采集与测定,内标法定量。结果发现,28种皮质激素在1. 0～100μg/L范围内具有良好的线性关系(R2>0. 99),方法检出限为0. 21～0. 48 ng/L,方法定量限为0. 32～0. 72 ng/L。在5. 0、10、50 ng/L的基质加标水平下,28种目标物的平均回收率为68. 8%～108. 7%,相对标准偏差为0. 1%～8. 1%。该方法灵敏、准确、可靠,将广泛应用于环境中糖/盐皮质激素的痕量监测及其行为、风险研究。

关键词：超高效液相色谱-串联质谱皮质激素地表水

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pH、温度及初始铊浓度对硫酸盐还原菌脱铊的影响

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环境工程学报 2014年第10期8卷 4105-4109页

作者：陈炜婷张鸿郭陈永亨罗定贵吴启航广州大学环境科学与工程学院珠江三角洲水质安全与保护省部共建重点实验室广州510006 国家海洋局南海环境监测中心广州510300

环境因素对硫酸盐还原菌除铊效果具有较大的影响。在对上流式厌氧污泥床污泥中分离纯化得到的硫酸盐还原菌进行初步鉴定的基础上,探讨pH、温度以及初始铊浓度对硫酸盐还原菌除铊效果的影响。实验结果表明,3株耐铊硫酸盐还原菌生长的反... 详细信息

环境因素对硫酸盐还原菌除铊效果具有较大的影响。在对上流式厌氧污泥床污泥中分离纯化得到的硫酸盐还原菌进行初步鉴定的基础上,探讨pH、温度以及初始铊浓度对硫酸盐还原菌除铊效果的影响。实验结果表明,3株耐铊硫酸盐还原菌生长的反应适宜pH为6.0,该pH环境下3个菌株的铊去除率分别为96.71%、97%和96.23%;最适温度在28~32℃范围内,此条件下3株菌株对铊的去除率分别高达93.11%、91.84%和92.83%;初始低浓度铊对菌株除铊效果影响较小,3株菌株除铊率均达到99.4%以上。对反应过程中的pH、温度以及初始铊浓度进行调节,对于改善硫酸盐还原菌去除铊污染效果具有重要意义。

关键词：硫酸盐还原菌铊 pH 温度初始浓度

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水环境中双酚A的污染及其生态毒理效应

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环境污染与防治 2009年第7期31卷 70-76页

作者：邓红梅梁春营陈永亨广州大学环境科学与工程学院广州市污染控制与同位素应用重点实验室广东广州510006

双酚A(BPA)广泛存在于水环境中,是一种雌激素,对人类健康和生态系统安全造成潜在威胁。BPA在各种水体中都有检出,且检出浓度有逐年增大的趋势;BPA在垃圾渗滤液、污水处理厂的出水及其污泥和沉积物中都能检出,且其浓度一般较地表水中的... 详细信息

双酚A(BPA)广泛存在于水环境中,是一种雌激素,对人类健康和生态系统安全造成潜在威胁。BPA在各种水体中都有检出,且检出浓度有逐年增大的趋势;BPA在垃圾渗滤液、污水处理厂的出水及其污泥和沉积物中都能检出,且其浓度一般较地表水中的浓度大。在综述了BPA在环境中的污染现状、迁移转化行为和生态毒理效应的研究进展基础上,指出了进一步研究BPA的重要性和今后的研究方向。

关键词：双酚A 吸附降解生态毒理效应

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A refined representation method of the particle size distribution curve based on grading entropy

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Particuology 2024年第5期88卷 302-311页

作者： Xing Li Qun chen Zhaozhao Liu cheng Zhou chen Wang chen chen State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

The particle size distribution(PSD)curve is an important expression of the basic properties of the *** characteristic parameters such as median particle size D_(50),effective particle size D_(10),and some combinations of characteristic parameters can only represent some points of the PSD curve,failing to represent all information of the PSD *** this paper,a fraction characteristic parameter F that could reflect the fraction size variation of the PSD curve was introduced based on grading *** a new presentation method of the A-B-F three parameters was proposed for a refined representation of the PSD *** was found that the newly constructed model not only better represents the differences in the width of PSD curves but also has a higher sensitivity than the A-B two-parameter model proposed by Lő*** PSD curves with similar distributions,the new presentation method has a higher degree of discrimination than that of the D_(50)-C_(u)-C_(c) three-parameter or the four-parameter combination G_(c) proposed by ***,the application of this new method in describing the spatial nonuniformity distribution of depositions and predicting the soil hydraulic conductivity was *** research results can provide a reference for the refined representation of PSD curves.

关键词： Grading entropy Particle size distribution curve Refined representation

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基于轻量化CenterNet的智能车辆目标检测算法

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华南理工大学学报（自然科学版） 2024年第8期52卷 45-55页

作者：岳永恒宁睿厚东北林业大学土木与交通学院黑龙江哈尔滨150040

针对当前目标检测算法参数较多,计算量较大,导致响应速度较慢,难以推广应用于智能车辆系统的问题,提出一种改进的CenterNet目标检测算法。即应用轻量化MobileNetV3网络替换原ResNet-50网络,降低计算量;应用深度可分离的PANet替换特征增... 详细信息

针对当前目标检测算法参数较多,计算量较大,导致响应速度较慢,难以推广应用于智能车辆系统的问题,提出一种改进的CenterNet目标检测算法。即应用轻量化MobileNetV3网络替换原ResNet-50网络,降低计算量;应用深度可分离的PANet替换特征增强网络,获得多尺度特征信息融合后的特征,并引入SimAM注意力机制在特征融合前强化目标特征关注度,再用SiLU激活函数替换原目标检测网络中的ReLU激活函数,增强网络学习能力。最后提出CPAN-ASFF模块对深度可分离的PANet输出多尺度特征图进行融合,提高目标检测精度。应用优化后的KITTI数据集对改进后的CenterNet目标检测算法进行训练及检测验证,结果表明:其平均准确率为80.7%,比原始Center⁃Net目标检测算法提高了12个百分点,其检测速度为65 f/s,其参数量为8.91 M,较原算法减少72.73%,改进后的算法在遮挡目标、重叠目标以及与背景相似目标的检测效果上表现更优。且在SODA10M数据集中,文中提出的算法的检测精度与速度也都优于当前主流算法。该研究对算法的优化及实验为智能车辆在实际工程中的应用奠定了技术支撑。

关键词：智能车辆目标检测无先验框 CenterNet 轻量化深度可分离卷积

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色调分区加权约束的色调平面保持相机特性化

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光学学报 2024年第9期44卷 293-303页

作者：尹永恒马龙李鹏沈阳建筑大学计算机科学与工程学院辽宁沈阳110168 沈阳建筑大学理学部辽宁沈阳110168

为了在色调平面保持优良性能的基础上,进一步提高相机特性化性能,本文提出了色调分区内加权约束的色调平面保持相机特性化方法,通过优化色调分区改进加权约束的色调平面保持相机特性化。首先,对样本RGB进行初步划分色调分区,然后,在色... 详细信息

为了在色调平面保持优良性能的基础上,进一步提高相机特性化性能,本文提出了色调分区内加权约束的色调平面保持相机特性化方法,通过优化色调分区改进加权约束的色调平面保持相机特性化。首先,对样本RGB进行初步划分色调分区,然后,在色调分区内结合色调角对分区内样本的特性化矩阵加权平均得到本分区的特性化变换矩阵,其中通过优化色调分区的数量和位置来提升总体性能。实验结果表明,在D65光源的三组光谱数据和两组相机数据的仿真实验和曝光改变实验,以及三组光源和42组相机数据的补充仿真实验下,本文提出的相机特性化方法的性能优于已有的色调平面保持方法,且优于高阶多项式、根多项式方法或者与之持平,说明优化色调分区应用于相机特性化方法能够提升色调平面保持的相机特性化性能。

关键词：颜色相机特性化色调平面保持加权约束优化色调分区

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Track correlation algorithm based on CNN-LSTM for swarm targets

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Journal of Systems Engineering and Electronics 2024年第2期35卷 417-429页

作者： chen Jinyang WANG Xuhua chen Xian Research Institute for National Defense Engineering Academy of Military SciencesLuoyang 471023China Information Engineering University Zhengzhou 450001China School of Computer Science and Technology Xidian UniversityXi’an 710071China

The rapid development of unmanned aerial vehicle(UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms only use part of the target location, speed, and other information for *** this paper, the artificial neural network method is used to establish the corresponding intelligent track correlation model and method according to the characteristics of swarm ***, a route correlation method based on convolutional neural networks (CNN) and long short-term memory (LSTM)Neural network is designed. In this model, the CNN is used to extract the formation characteristics of UAV swarm and the spatial position characteristics of single UAV track in the formation,while the LSTM is used to extract the time characteristics of UAV swarm. Experimental results show that compared with the traditional algorithms, the algorithm based on CNN-LSTM neural network can make full use of multiple feature information of the target, and has better robustness and accuracy for swarm targets.

关键词： track correlation correlation accuracy rate swarm target convolutional neural network(CNN) long short-term memory(LSTM)neural network

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Two-stage Planning Method for Energy Router Considering Its Optimal Operation in Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 605-616页

作者： Meifu chen Mingchao Xia Qifang chen School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China

An energy router can effectively optimize the network loss and power quality of distribution networks. The optimal configuration of the energy router is relatively complex because issues dynamically influence each other, such as the location of the energy router, optimal number and capacity of its ports, and building new distribution lines for the ports. Presently, there has been very few research studies on the practical problems for the energy router. In this paper, a planning model of an energy router combined with the distribution network is established, which fully exploits the active and reactive power control abilities of the energy router to optimize the operation of the grid. The configuration problem is decoupled into two stages. The upper layer determines the location of the energy router and the parameters of the candidate new distribution lines for the ports. The lower layer calculates the optimal configuration of the energy router by minimizing the total annual cost. Because of the same rated bus voltage in the distribution network, the existing structure of the energy router is changed to be more applicable for the distribution network, and then the power flow model of the energy router is also modified. Due to the nonlinearity of the model, the planning model is converted into a mixed-integer second-order cone model to solve efficiently. In addition, some core factors influencing the optimal scheme of the energy router are also analyzed in this paper. Simulation results show that the optimal scheme of the energy router can significantly improve the economic deployment of the energy router, and optimize the network loss and power quality of the distribution network.

关键词： Capacity allocation distribution network energy router optimal operation

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Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

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Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： chen chen QUAN Wei SHAO Zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced ***, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)

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